Vol. 17, issue 10, article # 5

Abstract:

The angular distribution of spontaneous fluorescence excited by laser radiation inside a spherical particle is considered. The position and the effective volume of fluorescence sources emitting in the particle are calculated numerically as functions of the particle radius in the case of one-, two-, and three-photon-excited fluorescence. Within the framework of the geometric optics, an equation is derived for the mean brightness of fluorescence from the front and rear particle hemispheres. It is shown that if the fluorescence source is located near the dark hemisphere, asymmetry arises in the angular distribution of spontaneous fluorescence in the forward/backward directions, and this asymmetry becomes more pronounced with the increasing number of photons involved in the process.